None.
1. Field of Invention
The present invention relates generally to hand tools of the type useful in metal working or machine shop environments.
More particularly, the invention relates to a hand tool that is specially adapted for use in assisting in the removal of metal chips that are generated during the drilling or machining and tapping of a blind hole in a metal work piece.
2. Description of Prior Art
Machining and tapping blind holes in a metal work piece results in the collection of metal chips in the bottom of the hole.
Removal of these metal chips is a manual process, and can be at times rather difficult because a build-up of chips are typically pressed into the bottom of the hole by the threading tap.
Removal of such chips typically involves the use of a slender pick or similar probe that is provided with a pointed end which is typically turned at an angle such as approximately 90 degrees from the longitudinal axis of the pick.
In this instance, removal of the chips requires manually probing the blind hole with the end of the pick, and twisting and turning the pick, in an effort to snag the chips at the bottom of the hole so that they can be pulled out with the pick.
However, this techniques often results in the breaking up of the compressed pile of chips at the bottom of the hole, or the chips pull apart as they are being drawn from the hole, and therefore requires multiple attempts to remove all of the chips from the hole.
It is also common to attempt removal of metal chips from a blind hole by blowing the chips from the hole with compressed air utilizing a nozzle connected to a compressed air source such as shop compressor.
However, effective use of compressed air is limited to instances where the chips are relatively few and not compressed in the bottom of the hole, such as after use of a pick for removal of most of the chips.
Thus, it is apparent that removal of chips from blind holes is a labor intensive process, and in certain instances such as in parts with multiple blind holes, can add substantially to the cost of the part.
Therefore, there is a need for a new and improved tool and technique for removal of chips from blind holes (i) that facilitates a more complete chip removal process as compared with prior use of a pick, and (ii) such that the time required to remove the chips is reduced as compared with prior chip removal techniques, and thus the efficiency associated therewith is increased and the labor time and thus the cost is reduced.
The general aim of the present invention is to provide a new and improved hand tool and associated technique adapted to facilitate virtually complete chip removal from a blind hole with a single chip-removing process.
A detailed objective is to achieve the foregoing by providing a hand tool that is adapted to grab the compressed chips at the bottom of the hole with a single turning or twisting action such that the chips can then be removed as the tool is withdrawn from the hole.
These and other objectives and advantages of the invention will become more apparent from the following detailed description when taken in conjunction with the accompanying drawings.
In a preferred embodiment, a hand tool according to the invention includes an elongated handle sized and provided with an outer shape and finish to be comfortably grabbed and manually turned, and a shank extending from one end of the handle coaxially therewith. The shank is formed with a chip-engaging free end portion in the form of self-threading or self-tapping threads that continue to and terminate in a point at the free end thereof. A pile of chips at the bottom of a blind hole is removed by inserting the free end of the threaded shank into the hole until the chips are encountered, turning the tool while applying a slight pressure such that the free end of the tool threads into the chips, and then pulling the free end of the tool from the hole to remove the chips threaded thereon.